Perhaps the most widely accepted understanding of the idea of personal freedom is that it can be defined in negative terms as absence of interference. My lecture begins by noting that, because the concept of interference is such a complex one, this general agreement has turned out to be compatible with a great deal of disagreement about the conditions under which it may be legitimate to claim that freedom has been infringed. I am chiefly concerned, however, with those writers who have wished to challenge the core assumption that freedom is best understood as absence of interference. Some doubt whether the presence of freedom is best defined in terms of an absence at all, and instead attempt to connect freedom with specific patterns of moral behaviour But other critics -- on whom my lecture will end by focusing -- agree that the presence of freedom is best understood as the absence of something, while arguing that freedom fundamentally consists in the absence not of acts of interference but rather of broader conditions of arbitrary domination and dependence. I conclude by noting some of the implications of this view of freedom for the proper conduct of democratic government.